1/* 2 * Copyright (C) 2007-2010 B.A.T.M.A.N. contributors: 3 * 4 * Marek Lindner, Simon Wunderlich 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of version 2 of the GNU General Public 8 * License as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, but 11 * WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 * General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 18 * 02110-1301, USA 19 * 20 */ 21 22#include "main.h" 23#include "hard-interface.h" 24#include "soft-interface.h" 25#include "send.h" 26#include "translation-table.h" 27#include "routing.h" 28#include "bat_sysfs.h" 29#include "originator.h" 30#include "hash.h" 31 32#include <linux/if_arp.h> 33 34#define MIN(x, y) ((x) < (y) ? (x) : (y)) 35 36struct batman_if *get_batman_if_by_netdev(struct net_device *net_dev) 37{ 38 struct batman_if *batman_if; 39 40 rcu_read_lock(); 41 list_for_each_entry_rcu(batman_if, &if_list, list) { 42 if (batman_if->net_dev == net_dev) 43 goto out; 44 } 45 46 batman_if = NULL; 47 48out: 49 rcu_read_unlock(); 50 return batman_if; 51} 52 53static int is_valid_iface(struct net_device *net_dev) 54{ 55 if (net_dev->flags & IFF_LOOPBACK) 56 return 0; 57 58 if (net_dev->type != ARPHRD_ETHER) 59 return 0; 60 61 if (net_dev->addr_len != ETH_ALEN) 62 return 0; 63 64 /* no batman over batman */ 65#ifdef HAVE_NET_DEVICE_OPS 66 if (net_dev->netdev_ops->ndo_start_xmit == interface_tx) 67 return 0; 68#else 69 if (net_dev->hard_start_xmit == interface_tx) 70 return 0; 71#endif 72 73 /* Device is being bridged */ 74 /* if (net_dev->priv_flags & IFF_BRIDGE_PORT) 75 return 0; */ 76 77 return 1; 78} 79 80static struct batman_if *get_active_batman_if(void) 81{ 82 struct batman_if *batman_if; 83 84 /* TODO: should check interfaces belonging to bat_priv */ 85 rcu_read_lock(); 86 list_for_each_entry_rcu(batman_if, &if_list, list) { 87 if (batman_if->if_status == IF_ACTIVE) 88 goto out; 89 } 90 91 batman_if = NULL; 92 93out: 94 rcu_read_unlock(); 95 return batman_if; 96} 97 98static void set_primary_if(struct bat_priv *bat_priv, 99 struct batman_if *batman_if) 100{ 101 struct batman_packet *batman_packet; 102 103 bat_priv->primary_if = batman_if; 104 105 if (!bat_priv->primary_if) 106 return; 107 108 set_main_if_addr(batman_if->net_dev->dev_addr); 109 110 batman_packet = (struct batman_packet *)(batman_if->packet_buff); 111 batman_packet->flags = PRIMARIES_FIRST_HOP; 112 batman_packet->ttl = TTL; 113 114 /*** 115 * hacky trick to make sure that we send the HNA information via 116 * our new primary interface 117 */ 118 atomic_set(&hna_local_changed, 1); 119} 120 121static bool hardif_is_iface_up(struct batman_if *batman_if) 122{ 123 if (batman_if->net_dev->flags & IFF_UP) 124 return true; 125 126 return false; 127} 128 129static void update_mac_addresses(struct batman_if *batman_if) 130{ 131 if (!batman_if || !batman_if->packet_buff) 132 return; 133 134 addr_to_string(batman_if->addr_str, batman_if->net_dev->dev_addr); 135 136 memcpy(((struct batman_packet *)(batman_if->packet_buff))->orig, 137 batman_if->net_dev->dev_addr, ETH_ALEN); 138 memcpy(((struct batman_packet *)(batman_if->packet_buff))->prev_sender, 139 batman_if->net_dev->dev_addr, ETH_ALEN); 140} 141 142static void check_known_mac_addr(uint8_t *addr) 143{ 144 struct batman_if *batman_if; 145 146 rcu_read_lock(); 147 list_for_each_entry_rcu(batman_if, &if_list, list) { 148 if ((batman_if->if_status != IF_ACTIVE) && 149 (batman_if->if_status != IF_TO_BE_ACTIVATED)) 150 continue; 151 152 if (!compare_orig(batman_if->net_dev->dev_addr, addr)) 153 continue; 154 155 pr_warning("The newly added mac address (%pM) already exists " 156 "on: %s\n", addr, batman_if->dev); 157 pr_warning("It is strongly recommended to keep mac addresses " 158 "unique to avoid problems!\n"); 159 } 160 rcu_read_unlock(); 161} 162 163int hardif_min_mtu(void) 164{ 165 struct batman_if *batman_if; 166 /* allow big frames if all devices are capable to do so 167 * (have MTU > 1500 + BAT_HEADER_LEN) */ 168 int min_mtu = ETH_DATA_LEN; 169 170 rcu_read_lock(); 171 list_for_each_entry_rcu(batman_if, &if_list, list) { 172 if ((batman_if->if_status == IF_ACTIVE) || 173 (batman_if->if_status == IF_TO_BE_ACTIVATED)) 174 min_mtu = MIN(batman_if->net_dev->mtu - BAT_HEADER_LEN, 175 min_mtu); 176 } 177 rcu_read_unlock(); 178 179 return min_mtu; 180} 181 182/* adjusts the MTU if a new interface with a smaller MTU appeared. */ 183void update_min_mtu(void) 184{ 185 int min_mtu; 186 187 min_mtu = hardif_min_mtu(); 188 if (soft_device->mtu != min_mtu) 189 soft_device->mtu = min_mtu; 190} 191 192static void hardif_activate_interface(struct net_device *net_dev, 193 struct bat_priv *bat_priv, 194 struct batman_if *batman_if) 195{ 196 if (batman_if->if_status != IF_INACTIVE) 197 return; 198 199 update_mac_addresses(batman_if); 200 batman_if->if_status = IF_TO_BE_ACTIVATED; 201 202 /** 203 * the first active interface becomes our primary interface or 204 * the next active interface after the old primay interface was removed 205 */ 206 if (!bat_priv->primary_if) 207 set_primary_if(bat_priv, batman_if); 208 209 bat_info(net_dev, "Interface activated: %s\n", batman_if->dev); 210 211 if (atomic_read(&module_state) == MODULE_INACTIVE) 212 activate_module(); 213 214 update_min_mtu(); 215 return; 216} 217 218static void hardif_deactivate_interface(struct net_device *net_dev, 219 struct batman_if *batman_if) 220{ 221 if ((batman_if->if_status != IF_ACTIVE) && 222 (batman_if->if_status != IF_TO_BE_ACTIVATED)) 223 return; 224 225 batman_if->if_status = IF_INACTIVE; 226 227 bat_info(net_dev, "Interface deactivated: %s\n", batman_if->dev); 228 229 update_min_mtu(); 230} 231 232int hardif_enable_interface(struct batman_if *batman_if) 233{ 234 struct bat_priv *bat_priv = netdev_priv(soft_device); 235 struct batman_packet *batman_packet; 236 237 if (batman_if->if_status != IF_NOT_IN_USE) 238 goto out; 239 240 batman_if->packet_len = BAT_PACKET_LEN; 241 batman_if->packet_buff = kmalloc(batman_if->packet_len, GFP_ATOMIC); 242 243 if (!batman_if->packet_buff) { 244 bat_err(soft_device, "Can't add interface packet (%s): " 245 "out of memory\n", batman_if->dev); 246 goto err; 247 } 248 249 batman_packet = (struct batman_packet *)(batman_if->packet_buff); 250 batman_packet->packet_type = BAT_PACKET; 251 batman_packet->version = COMPAT_VERSION; 252 batman_packet->flags = 0; 253 batman_packet->ttl = 2; 254 batman_packet->tq = TQ_MAX_VALUE; 255 batman_packet->num_hna = 0; 256 257 batman_if->if_num = bat_priv->num_ifaces; 258 bat_priv->num_ifaces++; 259 batman_if->if_status = IF_INACTIVE; 260 orig_hash_add_if(batman_if, bat_priv->num_ifaces); 261 262 atomic_set(&batman_if->seqno, 1); 263 bat_info(soft_device, "Adding interface: %s\n", batman_if->dev); 264 265 if (hardif_is_iface_up(batman_if)) 266 hardif_activate_interface(soft_device, bat_priv, batman_if); 267 else 268 bat_err(soft_device, "Not using interface %s " 269 "(retrying later): interface not active\n", 270 batman_if->dev); 271 272 /* begin scheduling originator messages on that interface */ 273 schedule_own_packet(batman_if); 274 275out: 276 return 0; 277 278err: 279 return -ENOMEM; 280} 281 282void hardif_disable_interface(struct batman_if *batman_if) 283{ 284 struct bat_priv *bat_priv = netdev_priv(soft_device); 285 286 if (batman_if->if_status == IF_ACTIVE) 287 hardif_deactivate_interface(soft_device, batman_if); 288 289 if (batman_if->if_status != IF_INACTIVE) 290 return; 291 292 bat_info(soft_device, "Removing interface: %s\n", batman_if->dev); 293 bat_priv->num_ifaces--; 294 orig_hash_del_if(batman_if, bat_priv->num_ifaces); 295 296 if (batman_if == bat_priv->primary_if) 297 set_primary_if(bat_priv, get_active_batman_if()); 298 299 kfree(batman_if->packet_buff); 300 batman_if->packet_buff = NULL; 301 batman_if->if_status = IF_NOT_IN_USE; 302 303 if ((atomic_read(&module_state) == MODULE_ACTIVE) && 304 (bat_priv->num_ifaces == 0)) 305 deactivate_module(); 306} 307 308static struct batman_if *hardif_add_interface(struct net_device *net_dev) 309{ 310 struct batman_if *batman_if; 311 int ret; 312 313 ret = is_valid_iface(net_dev); 314 if (ret != 1) 315 goto out; 316 317 dev_hold(net_dev); 318 319 batman_if = kmalloc(sizeof(struct batman_if), GFP_ATOMIC); 320 if (!batman_if) { 321 pr_err("Can't add interface (%s): out of memory\n", 322 net_dev->name); 323 goto release_dev; 324 } 325 326 batman_if->dev = kstrdup(net_dev->name, GFP_ATOMIC); 327 if (!batman_if->dev) 328 goto free_if; 329 330 ret = sysfs_add_hardif(&batman_if->hardif_obj, net_dev); 331 if (ret) 332 goto free_dev; 333 334 batman_if->if_num = -1; 335 batman_if->net_dev = net_dev; 336 batman_if->if_status = IF_NOT_IN_USE; 337 batman_if->packet_buff = NULL; 338 INIT_LIST_HEAD(&batman_if->list); 339 340 check_known_mac_addr(batman_if->net_dev->dev_addr); 341 list_add_tail_rcu(&batman_if->list, &if_list); 342 return batman_if; 343 344free_dev: 345 kfree(batman_if->dev); 346free_if: 347 kfree(batman_if); 348release_dev: 349 dev_put(net_dev); 350out: 351 return NULL; 352} 353 354static void hardif_free_interface(struct rcu_head *rcu) 355{ 356 struct batman_if *batman_if = container_of(rcu, struct batman_if, rcu); 357 358 /* delete all references to this batman_if */ 359 purge_orig(NULL); 360 purge_outstanding_packets(batman_if); 361 362 kfree(batman_if->dev); 363 kfree(batman_if); 364} 365 366static void hardif_remove_interface(struct batman_if *batman_if) 367{ 368 /* first deactivate interface */ 369 if (batman_if->if_status != IF_NOT_IN_USE) 370 hardif_disable_interface(batman_if); 371 372 if (batman_if->if_status != IF_NOT_IN_USE) 373 return; 374 375 batman_if->if_status = IF_TO_BE_REMOVED; 376 list_del_rcu(&batman_if->list); 377 sysfs_del_hardif(&batman_if->hardif_obj); 378 dev_put(batman_if->net_dev); 379 call_rcu(&batman_if->rcu, hardif_free_interface); 380} 381 382void hardif_remove_interfaces(void) 383{ 384 struct batman_if *batman_if, *batman_if_tmp; 385 386 list_for_each_entry_safe(batman_if, batman_if_tmp, &if_list, list) 387 hardif_remove_interface(batman_if); 388} 389 390static int hard_if_event(struct notifier_block *this, 391 unsigned long event, void *ptr) 392{ 393 struct net_device *net_dev = (struct net_device *)ptr; 394 struct batman_if *batman_if = get_batman_if_by_netdev(net_dev); 395 struct bat_priv *bat_priv = netdev_priv(soft_device); 396 397 if (!batman_if && event == NETDEV_REGISTER) 398 batman_if = hardif_add_interface(net_dev); 399 400 if (!batman_if) 401 goto out; 402 403 switch (event) { 404 case NETDEV_UP: 405 hardif_activate_interface(soft_device, bat_priv, batman_if); 406 break; 407 case NETDEV_GOING_DOWN: 408 case NETDEV_DOWN: 409 hardif_deactivate_interface(soft_device, batman_if); 410 break; 411 case NETDEV_UNREGISTER: 412 hardif_remove_interface(batman_if); 413 break; 414 case NETDEV_CHANGENAME: 415 break; 416 case NETDEV_CHANGEADDR: 417 check_known_mac_addr(batman_if->net_dev->dev_addr); 418 update_mac_addresses(batman_if); 419 if (batman_if == bat_priv->primary_if) 420 set_primary_if(bat_priv, batman_if); 421 break; 422 default: 423 break; 424 }; 425 426out: 427 return NOTIFY_DONE; 428} 429 430/* receive a packet with the batman ethertype coming on a hard 431 * interface */ 432int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, 433 struct packet_type *ptype, struct net_device *orig_dev) 434{ 435 struct bat_priv *bat_priv = netdev_priv(soft_device); 436 struct batman_packet *batman_packet; 437 struct batman_if *batman_if; 438 int ret; 439 440 skb = skb_share_check(skb, GFP_ATOMIC); 441 442 /* skb was released by skb_share_check() */ 443 if (!skb) 444 goto err_out; 445 446 if (atomic_read(&module_state) != MODULE_ACTIVE) 447 goto err_free; 448 449 /* packet should hold at least type and version */ 450 if (unlikely(skb_headlen(skb) < 2)) 451 goto err_free; 452 453 /* expect a valid ethernet header here. */ 454 if (unlikely(skb->mac_len != sizeof(struct ethhdr) 455 || !skb_mac_header(skb))) 456 goto err_free; 457 458 batman_if = get_batman_if_by_netdev(skb->dev); 459 if (!batman_if) 460 goto err_free; 461 462 /* discard frames on not active interfaces */ 463 if (batman_if->if_status != IF_ACTIVE) 464 goto err_free; 465 466 batman_packet = (struct batman_packet *)skb->data; 467 468 if (batman_packet->version != COMPAT_VERSION) { 469 bat_dbg(DBG_BATMAN, bat_priv, 470 "Drop packet: incompatible batman version (%i)\n", 471 batman_packet->version); 472 goto err_free; 473 } 474 475 /* all receive handlers return whether they received or reused 476 * the supplied skb. if not, we have to free the skb. */ 477 478 switch (batman_packet->packet_type) { 479 /* batman originator packet */ 480 case BAT_PACKET: 481 ret = recv_bat_packet(skb, batman_if); 482 break; 483 484 /* batman icmp packet */ 485 case BAT_ICMP: 486 ret = recv_icmp_packet(skb); 487 break; 488 489 /* unicast packet */ 490 case BAT_UNICAST: 491 ret = recv_unicast_packet(skb, batman_if); 492 break; 493 494 /* broadcast packet */ 495 case BAT_BCAST: 496 ret = recv_bcast_packet(skb); 497 break; 498 499 /* vis packet */ 500 case BAT_VIS: 501 ret = recv_vis_packet(skb); 502 break; 503 default: 504 ret = NET_RX_DROP; 505 } 506 507 if (ret == NET_RX_DROP) 508 kfree_skb(skb); 509 510 /* return NET_RX_SUCCESS in any case as we 511 * most probably dropped the packet for 512 * routing-logical reasons. */ 513 514 return NET_RX_SUCCESS; 515 516err_free: 517 kfree_skb(skb); 518err_out: 519 return NET_RX_DROP; 520} 521 522struct notifier_block hard_if_notifier = { 523 .notifier_call = hard_if_event, 524}; 525